#include<iostream>
#include<vector>
#include<queue>
#include<cstring>
#include<cmath>
#include<map>
#include<set>
#include<cstdio>
#include<algorithm>
#define debug(a) cout<<#a<<"="<<a<<endl;
using namespace std;
const int maxn=1e5+1000;
typedef long long LL;
inline LL read(){LL x=0,f=1;char ch=getchar();	while (!isdigit(ch)){if (ch=='-') f=-1;ch=getchar();}while (isdigit(ch)){x=x*10+ch-48;ch=getchar();}
return x*f;}
char str[maxn];
int main(void){
   cin.tie(0);std::ios::sync_with_stdio(false);
   LL t;cin>>t;
   while(t--){
      LL n;cin>>n;
      cin>>(str+1);
      map<char,LL>map1;
      for(LL i=1;i<=n;i++){
          if(str[i]=='M') map1['M']++;
          else map1['L']++;
      }
      if(2*map1['M']!=map1['L']){
         cout<<"NO"<<"\n";
         continue;
      }
      LL sum1=0;LL m=0;
      bool flag=1;
      for(LL i=1;i<=n;i++){
          if(str[i]=='T'){
             sum1++;
          }
          else{
             m++;
             if(sum1<m){
                flag=0;break;
             }
          }
      }
      sum1=0;m=0;
      for(LL i=n;i>=1;i--){
          if(str[i]=='T'){
             sum1++;
          }
          else{
             m++;
             if(sum1<m){
                flag=0;break;
             }
          }
      }
      if(flag){
         cout<<"YES"<<"\n";
      }
      else{
         cout<<"NO"<<"\n";
      }
   }
   return 0;
}
